.22 br brass issue

[Forward543]

Im shooting .22 br in gold box lapua brass. The initial size down was done via bushings in a 6bra die in 2 steps. The first firing shot well. Now i cant get them to shoot. I tried 22 br forster full length, honed with a .244 nk. I tried redding 6br with a .248 bushing and then bumping with a k and m neck turning mandrel. Is it possible residule imperial wax(using for mandrel) is causing neck tension issues?
My groups were sub .5 moa before the second sizing, now i have 1-2 fliers in a 5 shot group.
Ideas?

 

[lpreddick]

The case volumn in a new case is slightly smaller than ff and resized case, depending on fl die . Do you have MVs on new and ff cases? If ff case MV is less, you can bump charge by .2 gr powder and might find an accuracy node.

 

[chuckshooter]

Barrel twist? Bullet? Powder? For me I had to change up my bullet ,powder, and seating depth. I'm not convinced it's brass issue but what do I know

 

[stacy]

WHATS THE NK DIA OF YOUR CHAMBER?

 

[Forward543]

.254 neck. 7twist, 88 eld, h4895. Loaded round is .251.

 

[Terry]

How fast?

 

[stacy]

JUST DONT OVER BUMP UR SHOULDERS .002 WORKS WELL FOR ME SO A LOADED ROUND IS .251 LOADED SO UR NK'S ARE TURNED AROUND .012 IF SO TRY A .249 BUSHING,ONE OF MY 22BR'S ONLY LIKES .001 CLEARENCE

 

[Forward543]

How fast?

3000 fps in a 24" bartlein.

 

[22BRGUY]

Could be so many things. I'd try what lpreddick said and maybe mess with seating depth but from there I'd start from scratch with fireformed brass